The Autistic community often describes stimming (repetitive behaviours) as a helpful way to regulate themselves. But researchers have sometimes seen these repetitive actions as pointless or even concerning behaviours.​ We wanted to know what research has already been done on why Autistic adults stim, including to see if there are any clear gaps in work to date, so we conducted a scoping review of research on 'autism + stimming + function' in adults between 2013 - 2025. We found nine studies (see below) which met our criteria. Autistic adults say stimming helps them regulate their emotions and physical sensations in their body. Even though the studies found information on why Autistic people stim, most of them didn't initially intend to research this question. This means we still do not know much about why Autistic adults stim, or what stimming means to them, and we need more researchers to intentionally study why and how Autistic adults stim.